Mobile communications devices, including but not limited to cell phones, have become an integral part of society over the last two decades. On occasion, a mobile communication device may suffer a serious software error (sometimes called a fatal software error), which can be resolved by a reset operation. In early devices, a user could typically accomplish this reset operation by removing the power supply, i.e. a “battery pull” procedure. To avoid the inconvenience of the battery pull procedure, some manufacturers provided a reset switch that provided similar functionality, and other manufacturers made the reset function accessible via a software command. A reset operation in which the entire system is reset is often called a “hard reset operation” or a “full reset operation.”
The typical mobile communications device may include many integrated circuits (ICs) therein, for example, a processor such as a central processing unit (CPU), a power management circuit, and a graphics processing unit (GPU) driving a display for the device. Each of these ICs is supplied with power controlled by the power management circuit. When the device is reset, the power supplied to each of theses ICs is cycled off and on, thereby resetting all the ICs. Nonetheless, when these ICs are reset, the device may have a lengthy reboot time, thereby inconveniencing the user.